Improvement in method of casting metaz, pipes



thickness, the still liquid interior may be run by ele- `with the mould elevated, and the unset metal in the lanttdf Statut Intent @Biblica JOHN JOSEPH CHARLES SMITH, OF PHILADELPHIA, PENNSYLYANIA, ASSIGNOR TO THE METALLIC COMPRESSION CAS'IIING COMPANY, OF BOSTON, MASSACHUSETTS.

Leners Patent No. 90,201, daad .Ma/y 18, 1869.

JThe Schedule referred to in these Letters Patent and making part of tile. same.

To all whom 'it may concern:

Be it known that I, JOHN JOSEPH CHARLES SMITH, of the city and county of Philadelphia, and State of Pennsylvania, have invented a new and improved Process and Apparatus for Casting Tubes and other Hollow Articles of Hard or Refractory Metal; and I do hereby declare the following to be a full, clear, and exact-description of the same, reference being had to the accompanying drawings, which areV made a part of this specification.

My invention consists in casting tubes, and some other hollow articles, of iron, steel, or other hard or refractory metal, by running a charge of the metal into a mould of sufficiently free conducting-material, to cause the outer part of the moltenmeta'l to `set more quickly than the interior, so that, after a sufficient interval to form a shell or tube of the desired vating the mould, or opening? a gate in its lower part.

I`n order to enable one skilled in the art to which my invention appcrtains, to carry it into effect, I will proceed to describe an apparatus and mode of operation which I have used with good success in casting ironpipes from three-fourths of au inch to five inches in diameter.

In th drawings- Figure l represents an elevation of the apparatus, with the mould closed, for the reception ofthe molten metal.

Figure 2 represents a vertical section of the same,

act of running out.

Figure 3 represents a horizontal section 'of the mould and its accessories.

The mould A is made to open and close by means of hinges a a, and is attached to a slide, B, which works in a guide in the standard C, so that the mould may be elevated by a lever, D, or other means.

E represents a reservoir, attached removably to the top of the mould, and F, a band or ring, by which its lower end may be held together.

Within the funnel is a valve, G, 0f clay or otherinfusible and n0n-conductiug material, which is raised or opened, to allow the molten metal to pass instantaneously from the reservoir into the mould, when'the casting is to be performed.

The interior of the reservoir is lined with clay or other suitable nou-conducting material, to protect the fluid metal from setting.

Operation.

mould A. Everything being ready, the valve Gr is raised, permitting the molten metal to lw instantaneously into themetallic mould A, the contact of which chills the outer part of the molten mass sufficiently to harden it'before the internal part.

When the molten Inet-al has been in the mouldfrom two to live seconds, according to the size of the pipe to be produced, and the desired thickness of its walls, the mould A is elevated by the lever D, or other means, permitting the molten metal in the centre of the mould to flow out, as represented in fig. 2, leaving a tubular casting of the form, size, audthickness desired.-

The4 sand s prevents the chilling of the metal on the bottom of the mould, and permits the molten part to `flow out, without obstruction, when themould iselevated.

Instead of elevating the mould, it is manifest thatV the same result can be accomplished by providing a gate, to be opened, at its lower part, in orderto permit the escape of the metal. l

Whenrthe cast tube or other article has remained a suliicient time in the mould, the reservoir E and band F are removed, the mould opened, and the casting discharged. i

I am aware that hollow articles have been cast, of Britannia, zinc, and other soft metal, by what is known as the slashing-process; but I-am not aware that any practical mode has before been devised by which pipes and other long hollow articles can be cast, of iron, steel, or other refractory metal, by chilling the eXterior, and allowing the molten interior part to flow out.

In my process, it is necessary to employa reservoir, provided with a non-conducting lining, within which the molten metal may be kept in readiness for casting, and that the temporarily-closable opening between such reservoir and the mould shall he as large as the diameter of the mould itself, or of suilcient size to permit the `instantaneous passage of the metal from the reservoir int-o the mould, when the valve is opened.

In practice, it is found 'to be essential to the most advantageous use of this invention, that the discharge of the molten metal shall be directly downward from the centre of the lower part of the casting. By this means, I am enabled to produce tubes, and other articles with walls, of accurately-uniform thickness; but this uniformity is seriously impaired, if the liquid metal be allowed' to iiow out slowly over the inner surface of that which is newly set.

t It is my intent-ion to apply the invention to the casting oi' pipes and analogous long articles, such as hollow rails, beams, pillars, Sac., for architectural and engineering-purposes, as well as for the conduction of liuids also, to the casting of spheres and other bodies, when the same are to be madewith two orifices, so as to permitrthe discharge of the molten metal, in the manner explained.

vIn the case of iron, the castings may be made malleable, according tothe well-known process, and thus provide a cheapand perfectly-edicient substitute. for the wrought-iron pipes which are now produced, at great labor and cost, 'by welding and rolling. l

I amaware that the broad principle of castnghollow articlesby pouring the molten metal into the mould, and, after allowing a suflicient thickness of shell to congeal or harden, discharging the still molten intel rior, has been, for a long time, employed for` casting small articles of soft metal. I do not, therefore,-

5, broadly claim casting by that mode; but l What Ido claim as new, and of my invention, and

desire to secure by Letters Patent, is-

l. The apparatus adapted to receive the molten metal at top, and discharge a portion of it at bottom,

substantially as herein described, for the purposes stated.

2. In combination with the mould A, the-lined reservoir E and plug G, constructed and a-rranged'as de scribed, to provide for the instantaneous introduction of molten metal into the said mould.

3. The combination df the mould A', theunyielding base or gate S, by which the bottom of .the said mould may be opened or closed atpleasure, and a temporary bottom, s, of" ieldi'ng and non-conducting material, all being constluet'ed and arranged to operate'substantially as shown and described, for the purposes set forth. l V

Y JOHN .J OS.` OHASMSMITH.

Witnesses:

WM. H. BRERETQN, Jr., Ocmvrus KNIGHT. 

